Method for designing an ECS

ABSTRACT

An airplane is provided. The airplane includes an environmental control system that provides a pressurized medium to a chamber of the airplane. The airplane also includes a bleed system. The bleed system includes a plurality of ports, each of which can provide a bleed medium from an engine of the airplane to the environmental control system. The plurality of ports includes at least a first port, a second port, and a third port. The first port is selected for an idle condition. The second port is selected for a hot day cruise condition. The third port is selected for a standard operating condition. The bleed system can operate in a first mode, a second mode, or a third mode to provide the bleed medium to the environmental control system from the first port, the second port, or the third port respectively.

CROSS-REFERENCES TO RELATED APPLICATIONS

This patent application claims priority to U.S. Provisional PatentApplication Ser. No. 62/170,916, filed Jun. 4, 2015 which isincorporated herein by reference in its entirety.

BACKGROUND

In general, contemporary air condition systems are supplied a pressureat cruise that is approximately 30 psig to 35 psig. The trend in theaerospace industry today is towards systems with higher efficiency. Oneapproach to improve airplane efficiency is to eliminate the bleed airentirely and use electrical power to compress outside air. A secondapproach is to use lower engine pressure. The third approach is to usethe energy in the bleed air to compress outside air and bring it intothe cabin. Unfortunately, each of these approaches provides limitedefficiency with respect to engine fuel burn.

BRIEF DESCRIPTION

According to one embodiment, an airplane is provided. The airplanecomprises an environmental control system configured to provide apressurized medium to a chamber of the airplane; and a bleed systemcomprising a plurality of ports, each of the plurality of ports beingconfigured to provide a bleed medium from an engine of the airplane tothe environmental control system, wherein the plurality of portsincludes at least a first port selected for an idle condition, a secondport selected for a hot day cruise condition, and a third port selectedfor a standard operating condition, and wherein the bleed systemoperates in a first mode, a second mode, or a third mode to provide thebleed medium to the environmental control system from the first port,the second port, or the third port respectively.

According to one embodiment, a method of optimizing a bleed mediumprovided from a bleed system of an airplane to an environmental controlsystem of the airplane is provided. The method comprises analyzingoperational data of an engine of the airplane for a plurality of enginestages; choosing one or more bleed ports of the bleed system thatoptimally meet a required pressurization of a chamber of the airplanefor a plurality of flight segments, wherein the one or more bleed portsprovides the bleed medium to the environmental control system; andconfiguring the environmental control system to operate with the bleedmedium provided by the one or more bleed ports.

Additional features and advantages are realized through the techniquesof the embodiments herein. Other embodiments are described in detailherein and are considered a part of the claims. For a betterunderstanding of the embodiments with the advantages and the features,refer to the description and to the drawings

BRIEF DESCRIPTION OF THE DRAWINGS

The subject matter which is regarded as the present disclosure isparticularly pointed out and distinctly claimed in the claims at theconclusion of the specification. The foregoing and other features, andadvantages of the present disclosure are apparent from the followingdetailed description taken in conjunction with the accompanying drawingsin which:

FIG. 1 is a diagram of an schematic of an environmental control systemaccording to an embodiment;

FIG. 2 is a graph of a compression of an environmental control systemaccording to an embodiment;

FIG. 3 is another graph of a compression of an environmental controlsystem according to an embodiment;

FIG. 4 is a schematic of an example of a three port bleed configurationaccording to an embodiment;

FIG. 5 is operation example of an environmental control system thatutilizes additional bleed air, where the environmental control systemincludes an additional turbine, according to an embodiment;

FIG. 6 is operation example of an environmental control system thatutilizes cabin discharge air, where the environmental control systemincludes an additional turbine, according to another embodiment;

FIG. 7 is a schematic of an example of an environmental control systemthat utilizes a motor according to another embodiment; and

FIG. 8 a schematic of an example of a mechanically powered bleedconfiguration according to another embodiment.

DETAILED DESCRIPTION

A detailed description of one or more embodiments of the disclosedapparatus and method are presented herein by way of exemplification andnot limitation with reference to the FIGS.

Embodiments herein provide a method of selecting a bleed port on anengine that is suitable to provide a medium for cabin pressurization athigh fuel burn efficiency and an environmental control system to workwith that bleed port. The medium can generally be air, while otherexamples include gases, liquids, fluidized solids, or slurries.

Turning to FIG. 1, a system 100 that receives a medium from an inlet 101and provides a conditioned form of the medium to a chamber 102 isillustrated. The system 100 comprises a compressing device 110. Asshown, the compressing device 110 comprises a compressor 112, a turbine113, a fan 116, and a shaft 118. The system 100 also comprises a primaryheat exchanger 120, a secondary heat exchanger 130, a reheater 160, acondenser 162, and a water extractor 164.

The compressing device 110 is a mechanical device that includescomponents for performing thermodynamic work on the medium (e.g.,extracts or works on the medium by raising and/or lowering pressure andby raising and/or lowering temperature). Examples of the compressingdevice 110 include an air cycle machine, a three-wheel machine, a fourwheel-machine, etc.

The compressor 112 is a mechanical device that raises the pressure ofthe medium received from the inlet 101. Examples of compressor typesinclude centrifugal, diagonal or mixed-flow, axial-flow, reciprocating,ionic liquid piston, rotary screw, rotary vane, scroll, diaphragm, airbubble, etc. Further, compressors can be driven by a motor or the mediumvia the turbine 113.

The turbine 113 is mechanical device that drives the compressor 112 andthe fan 116 via the shaft 118. The turbine 113 can include a pluralityof inlet gas flow paths, such as an inner flow path and an outer flowpath, to enable mixing of alternative medium flows at the exit of theturbine. The inner flow path can be a first diameter, and the outer flowpath can be a second diameter. The fan 116 (e.g., a ram air fan) is amechanical device that can force via push or pull methods air throughthe shell 119 across the heat exchangers 120 and 130 at a variablecooling to control temperatures. The shell 119 receives and directs amedium (such as ram air) through the system 100. In general, ram air isoutside air used as a heat sink by the system 100.

The heat exchangers 120 and 130 are devices built for efficient heattransfer from one medium to another. Examples of heat exchangers includedouble pipe, shell and tube, plate, plate and shell, adiabatic wheel,plate fin, pillow plate, and fluid heat exchangers.

The condenser 162 and the reheater 160 are particular types of heatexchangers. The water extractor 164 is a mechanical device that performsa process of taking water from the medium. Together, the condenser 162,the water extractor 164, and/or the reheater 160 can combine to be ahigh pressure water separator.

The elements of the system 100 are connected via valves, tubes, pipes,and the like. Valves (e.g., flow regulation device or mass flow valve)are devices that regulate, direct, and/or control a flow of a medium byopening, closing, or partially obstructing various passageways withinthe tubes, pipes, etc. of the system 100. Valves can be operated byactuators, such that flow rates of the medium in any portion of thesystem 100 can be regulated to a desired value.

As shown in FIG. 1, the medium can flow from an inlet 101 through thesystem 100 to a chamber 102, as indicated by solid-lined arrows. A valveV1 (e.g., a mass flow control valve) controls the flow of the mediumfrom the inlet 101 to the system 100. Further, a valve V2 controlswhether the flow of the medium from the secondary heat exchanger 130bypasses the condenser 162 in accordance with a mode of the system 100.A combination of components of the system 100 can be referred to as anair conditioning pack or a pack. The pack can begin at a valve V1 andconclude as air exits the condenser 162. An interface of the pack (apack interface) can be at the valve V1.

The system 100 will now be described in view of the above aircraftembodiment. In the aircraft embodiment, the medium can be air and thesystem 100 can be an environmental control system. The air supplied tothe environmental control system at the inlet 101 can be said to be“bled” from a turbine engine or an auxiliary power unit. When the air isbeing provided by the turbine engine or the auxiliary power unitconnected to the environmental control system, such as from the inlet101, the air can be referred to as bleed air (e.g., pressurized air thatcomes from an engine or an auxiliary power unit). The temperature,humidity, and pressure of the bleed air vary widely depending upon acompressor stage and revolutions per minute of the turbine engine.

The bleed air supplied to the system 100 can be provided by a bleedsystem. The bleed system can include a plurality of ports. In anembodiment, a method of selecting a bleed port on an engine that issuitable to provide the medium for cabin pressurization at high fuelburn efficiency to the system is provided.

The method includes receiving engine data from original equipmentmanufacturers. The engine data can include pressure and temperaturecombinations of the bleed air for every stage on the engine with respectto all flight segments. For example, a first segment can include groundidle, a second segment can include taxi, a third segment can includeclimb, a fourth segment can include cruise, a fifth segment can includedescend, and a sixth segment can include hold. Other examples of flightsegments include take-off, send again, etc. Note that one or more fightsegments can be placed into buckets to ease the evaluation of the enginedata.

The method also includes choosing one or more bleed ports that optimallymeet a required cabin pressurization for all flight segments. Forinstance, to optimally meet the required cabin pressurization, eachchosen bleed port can yield a bleed pressure slightly above or near therequired cabin pressurization. Each bleed pressure that is slightlyabove or near the required cabin pressurization can be a pressureselected from a range of 2.5 psi below the required cabin pressurizationto 5 psi greater than the required cabin pressurization. The one or morechosen bleed ports will be a first set of ports. From the first set ofports, a second set of one or more ports are chosen based on which arethe most universal all of the for all flight segments.

For example, after applying the above method, three modes wereidentified. Mode A identified a bleed port at an early stage along onthe engine (e.g., a low pressure port). The low pressure port can beused for climb and cruise flight segments. The low pressure port canalso be a bleed port that is in-between spools of the engine.

Mode B identified a bleed port at a late stage along on the engine(e.g., a high pressure port). The high pressure port can be arranged ator near high spool compressor discharge of an engine. The high pressureport can be used for descend, ground idle, and taxi flight segments(e.g., used when the engine is operating at an idle speed).

Mode C identified a bleed port at a stage between the early and latestage of the engine (e.g., an intermediate pressure port). Theintermediate pressure port can be used for a hold flight segment. Notethat once the method has selected the one or more bleed ports, thesystem can subsequently be modified to work with that bleed port.

In view of the above, the method of selecting the bleed port on theengine that is suitable to provide the bleed air for cabinpressurization at high fuel burn efficiency will now be described. Inthis example, the intermediate pressure port is initially utilized forall operating conditions outside of idle speed, such as take-off, climb,cruise, hold, etc. The intermediate pressure port is arranged within theengine based on a highest altitude and hottest day flight condition(e.g., a hot day cruise condition). However, outside of this hot daycruise condition, energy within the bleed air from the intermediatepressure port is wasted.

For example, FIG. 2 shows a graph 200 of a compression of anenvironmental control system (e.g., 100) according to an embodiment. Thegraph 200 illustrates a bleed pressure comparison with respect toselecting a location of the intermediate pressure port within the enginebased on the hot day cruise condition. That is, the graph 200 shows anend result of basing bleed port selection based on the hot day cruisecondition.

The graph 200 illustrates a y-axis 205 indicating pressure and an x-axis210 indicating altitude (at a factor of 1000 feet). Further, the graphillustrates a cabin pressure 215 (at a first pressure A), a requiredpressure 220 (at a second pressure B), a bleed pressure 225, a pressureat a pack interface 230, and a waste area 235. During the hot day cruisecondition, such as when an airplane is cursing at 43,000 feet on a hotday, there is very little or no wasted bleed pressure 225 (or energy).This hot day cruise condition represents less than 15% of actual flightconditions of the airplane. That is, in every other flight condition or85% of operational airplane time, there is a significant amount of waste(e.g., as indicated by the waste area 235).

To avoid this significant amount of waste, the intermediate pressureport can be arranged within the engine based on normal cruisingaltitudes and flight temperatures of standard operating conditions(e.g., the intermediate pressure port can be optimized for 85% of theactual flight conditions of the airplane). During standard operatingconditions, less energy within the bleed air from the intermediatepressure port is wasted than in the hot day cruise condition.

For example, FIG. 3 shows a graph 300 of a compression of anenvironmental control system (e.g., 100) according to an embodiment. Thegraph 300 illustrates a bleed pressure comparison with respect toselecting a location of the intermediate pressure port within the enginebased on the standard operating condition. That is, the graph 300 showsan end result of basing bleed port selection based on 85% of the actualflight conditions of the airplane.

Components of the graph 300 that are similar to the graph 200 have beenreused for ease of explanation, by using the same identifiers, and arenot re-introduced. The graph 300 illustrates a required pressure 320 (ata third pressure C), a bleed pressure 325, a pressure at a packinterface 330, and a waste area 335. Note that in graph 300, therequired pressure 315 is lower than the required pressure 215 (e.g., thethird pressure C is closer to the first pressure A than the secondpressure B). Further, note that the amount of waste has beensignificantly reduced (e.g., the waste area 335 is less than waste area235, as the slope of the bleed pressure 225 and bleed pressure 325 isthe same), and therefore the energy used by the system 100 is reduced bya third to a half.

Yet, a challenge is inherent to selecting the intermediate bleed portwith respect to the standard operating conditions as the pressure at thepack interface 330 drops below the required pressure 320 for the hot daycruise condition. Embodiments of the system 100 will now be describedthat address this challenge.

In an embodiment to address the challenge of the hot day cruisecondition, FIG. 4 illustrates an example of a three port bleed system400 utilized by the system 100. The three port bleed system 400 includesa precooler 410 and a plurality of valves V4.A, V4.B, V4.C, V4D, andV4.E. The precooler 410 can be designed to provide 400° F. to 450° F.air. The three port bleed system 400 also includes an engine 405 thatprovides bleed air from a plurality of ports (a first port 415, a secondport 420, and a third port 425).

The first port 415 can be a high pressure port used for engine idleconditions, thereby being applicable to cause the three port bleedsystem 400 to operate in the Mode B described above. The second port 420can be an intermediate pressure port used for hot-day cruisehigh-altitude cruise and/or for holding in icing conditions, therebybeing applicable to cause the three port bleed system 400 to operate inthe Mode C described above. The third port 425 can be a low pressureport used for take-off, climb, nominal-cruise, etc., thereby beingapplicable to cause the three port bleed system 400 to operate in theMode A described above. A location of the third port 425 is arrangedwithin the engine 405 based on the standard operating conditions. Also,fan air 430 can be extracted from a fan stream and utilized by theprecooler 410 to receive heat rejected from bleed air from either of thefirst or second ports 415 and 420. Note that, when the third port 425 isselected, the precooler 410 can be bypassed. By bypassing the precooler410 in this way, the precooler 410 can be optimized for the second port420. With respect to the above method, the system 100 can be configured(or modified) to work with the bleed ports 415, 420, and 425 of thethree port bleed system 400. To work with the bleed ports 415, 420, and425, the system 100 is configured to augment the bleed pressure slightlyabove or near the required cabin pressurization. The result of thisconfiguration can be one or more of a reduction of size of the precooler410, a bypassing of the precooler 410, and a deletion of the precooler410. That is, if the three port bleed system 400 enables bleed portswith temperatures below an auto-ignition temperature of fuel, then theprecooler 410 can be bypassed or deleted all together. Otherwise, if theprecooler 410 is needed for certain operating condition, then theprecooler 410 can be a reduced size to meet those conditions.

For example, the selection of the second port 420 can be based on thehot day cruise condition and/or on the airplane hold condition in icingconditions, so that parameters surrounding these conditions can be usedto size the precooler 410. That is, if the hot day cruise condition isselected, an airplane's fuel burn is optimized for a small amount offight conditions that occur on hot days, while a size and a weight ofthe precooler 410 can be reduced. If the holding in icing conditions isselected, a small amount of performance is sacrificed at the hot daycruise condition, while the size and the weight of the precooler 410 canbe greatly reduced. The reduction in the size and the weight of theprecooler 410 provides additional benefits for a majority of cruiseconditions.

In other embodiments to address the challenge of the hot day cruisecondition, FIGS. 5-8 are discussed. FIGS. 5-8 illustrate examples ofaugmenting power so that the system 100 can work with the intermediatepressure port that has the engine location based on the standardoperating condition.

Turning to FIG. 5, a schematic of an environmental control system 500 isprovided. The environmental control system 500 is a modification of thesystem 100, by including an additional energy source to meet thechallenge of the hot day cruise condition. Components of the system 500that are similar to the system 100 have been reused for ease ofexplanation, by using the same identifiers, and are not re-introduced.Alternative components of the environmental control system 500 include acompressing device 510 (that comprises a compressor 512, a turbine 513,a turbine 514, a fan 516, and a shaft 518), an outlet 554, a condenser560.

The turbine 514 is additional turbine mounted on the shaft 518 of thecompressing device 510 that receives bleed air from the engine. Forexample, a path for the bleed air flows from inlet 101 though valve V5and the turbine 514 to the outlet 554. Note that in one or moreembodiments, an exhaust from the turbine 514 can be released to ambientair through the shell 119 or sent to the outlet 545 (e.g., a cabinpressure control system). This bleed air is extracted from the engineand expanded across the turbine 514 for hot day cruise conditions. Thecompressor 512 is used to boost the bleed pressure based on power fromboth the turbine 513 and the turbine 514.

Turning to FIG. 6, a schematic of an environmental control system 600 isprovided. The environmental control system 600 is a modification of thesystem 100, by including an additional energy source to meet thechallenge of the hot day cruise condition. Components of the system 600that are similar to the system 100 have been reused for ease ofexplanation, by using the same identifiers, and are not re-introduced.Alternative components of the environmental control system 600 include acompressing device 610 (that comprises a compressor 612, a turbine 613,a turbine 614, a fan 616, and a shaft 618), an outlet 654, a reheater660, and a condenser 662.

The turbine 614 is additional turbine mounted on the shaft 618 of thecompressing device 5610 that receives cabin discharge air from thechamber 102 (e.g., a path for the cabin discharge air flows from chamber102 though valve V6.B and the turbine 614 to the outlet 654). The cabindischarge air is air being provided from the chamber 102 (e.g., airleaving a pressurized volume, cabin of the aircraft, or cabin and flightdeck of the aircraft). The cabin discharge air can be referred aschamber discharge air, pressured air. Note that in one or moreembodiments, an exhaust from the turbine 614 can be released to ambientair through the shell 119 or sent to the outlet 645 (e.g., a cabinpressure control system). This cabin discharge air is extracted from thechamber 102 and expanded across the turbine 614 for hot day cruiseconditions. The compressor 612 is used to boost the bleed pressure basedon power from both the turbine 613 and the turbine 614.

Turning to FIG. 7, a schematic of an environmental control system 700 isprovided. The environmental control system 700 is a modification of thesystem 100, by including an additional energy source to meet thechallenge of the hot day cruise condition. Components of the system 700that are similar to the system 100 have been reused for ease ofexplanation, by using the same identifiers, and are not re-introduced.Alternative components of the environmental control system 700 includean inlet 701 comprising a schematic of a bleed system. This bleed systemincludes an engine 702, auxiliary power unit 703, and a precooler 704,along with an alternative low pressure path for bleed air from theengine 702 that bypasses the precooler 704. Alternative components ofthe environmental control system 700 also include a compressing device710 (that comprises a compressor, turbines, a fan, a shaft, and a motor715) and heat exchangers 720 and 730.

The motor 715 can utilize electrical power. In this approach, electricalpower is used to drive the compressor of the compressing device 710. Thecompressing device 710 or an additional turbo machine can be used toboost the pressure.

The motor 715 can utilize hydraulic power. In this approach, hydraulicpower is used to drive the compressor of the compressing device 710. Thecompressing device 710 or an additional turbo machine can be used toboost the pressure.

Turning to FIG. 8, a schematic of bleed system 800 of an environmentalcontrol system is provided. The bleed system 800 includes a compressor801 mounted on a gear box 803 of an engine 805 to meet the challenge ofthe hot day cruise condition. Components of the system 800 that aresimilar to the system 400 have been reused for ease of explanation, byusing the same identifiers, and are not re-introduced. In thismechanical power approach, air shaft horsepower is used to drive thecompressor 801 that then supplies bled air to the environmental controlsystem through valve V8 via inlet 101.

In view of the above, an embodiment includes an airplane. The airplanecomprises an environmental control system configured to provide apressurized medium to a chamber of the airplane; and a bleed systemcomprising a plurality of ports, each of the plurality of ports beingconfigured to provide a bleed medium from an engine of the airplane tothe environmental control system, wherein the plurality of portsincludes at least a first port selected for an idle condition, a secondport selected for a hot day cruise condition, and a third port selectedfor a standard operating condition, and wherein the bleed systemoperates in a first mode, a second mode, or a third mode to provide thebleed medium to the environmental control system from the first port,the second port, or the third port respectively.

In another embodiment or the above airplane embodiment, the first portcan comprise a high pressure port and the first mode can be used for theidle condition.

In another embodiment or any of the above airplane embodiments, thesecond port can comprise an intermediate pressure port and the secondmode can be used for the hot day cruise condition.

In another embodiment or any of the above airplane embodiments, thethird port can comprise a low pressure port and the third mode can beused for at for the standard operating condition.

In another embodiment or any of the above airplane embodiments, thebleed system can comprise a precooler.

In another embodiment or any of the above airplane embodiments, theprecooler can be bypassed by the bleed medium during the third mode.

In another embodiment or any of the above airplane embodiments, theenvironmental control system can comprise a compressing devicecomprising a compressor configured to pressurize the bleed medium.

In another embodiment or any of the above airplane embodiments, thecompressing device can comprise a motor to provide power to thecompressor.

In another embodiment or any of the above airplane embodiments, themotor can be an electrically powered motor.

In another embodiment or any of the above airplane embodiments, themotor can be a hydraulically powered motor.

In another embodiment or any of the above airplane embodiments, thecompressing device can comprise a turbine to provide power to thecompressor.

In another embodiment or any of the above airplane embodiments, theturbine can be configured to receive the bleed medium.

In another embodiment or any of the above airplane embodiments, theturbine can be configured to receive a discharge medium from thechamber.

In another embodiment or any of the above airplane embodiments, thebleed system can comprise a turbine coupled to a gearbox of the engineand be configured pressurize the bleed medium.

In view of the above, an embodiment includes a method of optimizing ableed medium provided from a bleed system of an airplane to anenvironmental control system of the airplane. The method comprisesanalyzing operational data of an engine of the airplane for a pluralityof engine stages; choosing one or more bleed ports of the bleed systemthat optimally meet a required pressurization of a chamber of theairplane for a plurality of flight segments, wherein the one or morebleed ports provides the bleed medium to the environmental controlsystem; and configuring the environmental control system to operate withthe bleed medium provided by the one or more bleed ports.

In another embodiment or the above method embodiment, the environmentalcontrol system can comprise a compressing device comprising a compressorconfigured to pressurize the bleed medium, and the configuring of theenvironmental control system can comprise augmenting the pressurizationof the bleed medium by providing power to the compressor via a motor.

In another embodiment or the above method embodiment, the motor can bean electrically powered motor.

In another embodiment or the above method embodiment, the motor can be ahydraulically powered motor.

In another embodiment or the above method embodiment, the environmentalcontrol system can comprise a compressing device comprising a compressorconfigured to pressurize the bleed medium, and the configuring of theenvironmental control system can comprise augmenting the pressurizationof the bleed medium by providing power to the compressor via a turbine.

In another embodiment or the above method embodiment, the turbine can beconfigured to receive the bleed medium.

In another embodiment or the above method embodiment, the turbine can beconfigured to receive a discharge medium from the chamber.

In another embodiment or the above method embodiment, the bleed systemcan comprise a turbine coupled to a gearbox of the engine, and theturbine can be configured pressurize the bleed medium.

In another embodiment or the above method embodiment, the engine datacan comprise pressure and temperature combinations of the bleed air forevery stage on the engine with respect to a plurality of flightsegments.

In another embodiment or any of the above method embodiments, theplurality of flight segments can comprise a first segment includingground idle, a second segment including taxi, a third segment includingclimb, a fourth segment including cruise, a fifth segment includingdescend, and a sixth segment including hold.

In another embodiment or any of the above method embodiments, each ofthe one or more bleed ports can yield a bleed pressure above therequired pressurization.

In another embodiment or any of the above method embodiments, the bleedsystem can operate in a first mode, a second mode, or a third mode toprovide the bleed medium to the environmental control system from afirst port, a second port, or a third port, respectively, the one ormore bleed ports.

Aspects of the embodiments are described herein with reference toflowchart illustrations, schematics, and/or block diagrams of methods,apparatus, and/or systems according to embodiments. Further, thedescriptions of the various embodiments have been presented for purposesof illustration, but are not intended to be exhaustive or limited to theembodiments disclosed. Many modifications and variations will beapparent to those of ordinary skill in the art without departing fromthe scope and spirit of the described embodiments. The terminology usedherein was chosen to best explain the principles of the embodiments, thepractical application or technical improvement over technologies foundin the marketplace, or to enable others of ordinary skill in the art tounderstand the embodiments disclosed herein.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting. As used herein, thesingular forms “a”, “an” and “the” are intended to include the pluralforms as well, unless the context clearly indicates otherwise. It willbe further understood that the terms “comprises” and/or “comprising,”when used in this specification, specify the presence of statedfeatures, integers, steps, operations, elements, and/or components, butdo not preclude the presence or addition of one more other features,integers, steps, operations, element components, and/or groups thereof.

The flow diagrams depicted herein are just one example. There may bemany variations to this diagram or the steps (or operations) describedtherein without departing from the spirit of embodiments herein. Forinstance, the steps may be performed in a differing order or steps maybe added, deleted or modified. All of these variations are considered apart of the claims.

While the preferred embodiment has been described, it will be understoodthat those skilled in the art, both now and in the future, may makevarious improvements and enhancements which fall within the scope of theclaims which follow. These claims should be construed to maintain theproper protection.

The invention claimed is:
 1. An airplane comprising: an environmentalcontrol system configured to provide a pressurized medium to a chamberof the airplane, the environmental control system including compressingdevice comprising a compressor, a first turbine, a second turbine, and afan mounted to a shaft; and a bleed system comprising a plurality ofports, each of the plurality of ports being configured to provide ableed medium from an engine of the airplane to the environmental controlsystem, wherein the plurality of ports includes at least a first portselected for an idle condition, a second port selected for a hot daycruise condition, and a third port selected for a standard operatingcondition, wherein a pressure of the bleed medium provided via thesecond port is near the required cabin pressurization during a hot daycruise condition wherein the bleed system operates in a first mode, asecond mode, or a third mode to provide the bleed medium to theenvironmental control system from the first port, the second port, orthe third port respectively; wherein the second port is an intermediatepressure port, and during the hot day cruise condition, a first portionof the bleed medium provided from the second bleed port is expandedacross the second turbine and is exhausted to ambient, and a secondportion of the bleed medium is provided to the compressor to pressurizethe bleed medium, the compressor being driven by power from both thefirst turbine and the second turbine.
 2. The system of claim 1, whereinthe first port comprises a high pressure port and the first mode is usedfor the idle condition.
 3. The system of claim 1, wherein the bleedsystem includes a precooler.
 4. The system of claim 3, wherein theprecooler is bypassed by the bleed medium during the third mode.
 5. Thesystem of claim 1, wherein the compressing device comprises: a motor toprovide power to the compressor.
 6. The system of claim 5, wherein themotor is an electrically powered motor.
 7. The system of claim 5,wherein the motor is a hydraulically powered motor.
 8. The system ofclaim 1, wherein at least one of the first turbine and the secondturbine is configured to receive the bleed medium.
 9. The system ofclaim 1, wherein at least one of the first turbine and the secondturbine is configured to receive a discharge medium from the chamber.10. The system of claim 1, wherein the bleed system comprises: acompressor coupled to a gearbox of the engine and configured pressurizethe bleed medium.
 11. A method of optimizing a bleed medium providedfrom a bleed system of an airplane to an environmental control system ofthe airplane, the environmental control system including compressingdevice comprising a compressor, a first turbine, a second turbine, and afan mounted to a shaft, the method comprising: analyzing operationaldata of an engine of the airplane for a plurality of engine stages;choosing a plurality of bleed ports of the bleed system that optimallymeet a required pressurization of a chamber of the airplane for aplurality of flight segments, wherein one of the plurality of bleedports is positioned such that a pressure of the bleed medium providedthere through is near the required cabin pressurization during a hot daycruise condition of the plurality of flight segments, wherein theplurality of bleed ports provides the bleed medium to the environmentalcontrol system; and configuring the environmental control system tooperate with the bleed medium provided by the one or more bleed ports,wherein the one or more bleed ports comprises an intermediate pressureport operable to provide bleed medium at an intermediate pressure forthe hot day cruise condition and a lower pressure port operable toprovide bleed medium at a first pressure to the environmental controlsystem during a standard operating condition of the plurality to flightsegments, the first pressure being lower than the intermediate pressure;wherein during the hot day cruise condition, a first portion of thebleed medium provided from the second bleed port is expanded across thesecond turbine and is exhausted to ambient, and a second portion of thebleed medium is provided to the compressor, the compressor being drivenby power from both the first turbine and the second turbine.
 12. Themethod of claim 11, wherein the environmental control system comprises acompressing device comprising a compressor configured to pressurize thebleed medium, and wherein the configuring of the environmental controlsystem comprises: augmenting the pressurization of the bleed medium byproviding power to the compressor via a motor.
 13. The method of claim12, wherein the motor is an electrically powered motor.
 14. The methodof claim 12, wherein the motor is a hydraulically powered motor.
 15. Themethod of claim 11, wherein at least one of the first turbine and thesecond turbine is configured to receive the bleed medium.
 16. The methodof claim 11, wherein at least one of the first turbine and the secondturbine is configured to receive a discharge medium from the chamber.17. The method of claim 11, wherein the bleed system comprises acompressor coupled to a gearbox of the engine and wherein the turbine isconfigured pressurize the bleed medium.
 18. The method of claim 11,wherein the engine data comprises pressure and temperature combinationsof the bleed air for every stage on the engine with respect to aplurality of flight segments.
 19. The method of claim 11, wherein theplurality of flight segments comprises a first segment including groundidle, a second segment including taxi, a third segment including climb,a fourth segment including cruise, a fifth segment including descend,and a sixth segment including hold.
 20. The method of claim 11, whereineach of the plurality of bleed ports yields a bleed pressure slightlyabove or near the required pressurization.
 21. The method of claim 11,wherein the bleed system operates in a first mode, a second mode, or athird mode to provide the bleed medium to the environmental controlsystem from a first port, a second port, or a third port, respectively,of the plurality of bleed ports.